After the party has been living in Silverrock Castle for a short while, they begin to hear strange noises at night. It sounds as if a rumbling, growling noise is coming from beneath them. Upon attempting to locate the source of the noise, the party follows the sounds to the basement of the building in the southeast corner of the main courtyard. What is going on? Can the players keep living in Silverrock Castle?

This quest is intended for use in the larger quest "To Build A City", although it could be used in most campaigns as a short adventure.

This quest is a classic dungeon crawl. It allows the owners of Silverrock Castle to discover and explore a new section of their base, the dungeons and siege tunnels, as well as a network of natural tunnels that have been connected to the siege tunnels.

Many years ago, time beyond reckoning, a powerful druid made his home deep in a forest. His favorite grove was right where Silverrock Castle now stands. It was there that he was born, there that he spent much of his time, and there he eventually died fighting a great evil spreading through his forest. But this grove never fell. This grove continued to be protected by his magic, even after the land changed greatly. The earth slowly filled in around it, burying it in a cavern. It was sealed until water from the river above slowly etched away the tunnel network. A band of devils went to investigate, and it was their influence that eventually lead to the abandonment of Silverrock Castle. When the castle was abandoned, these devils were sealed inside, until a young dragon exploring a new den released them.

After the party has been living in Silverrock Castle for a short while, they begin to hear strange noises at night. It sounds as if a rumbling, growling noise is coming from beneath them. Upon attempting to locate the source of the noise, the party follows the sounds to the basement of the building in the southeast corner of the main courtyard. This building was being used as a storehouse by the bandits, and chances are, probably something similar by the PCs. If the party looks around and listens, they can hear that the sounds seem to be coming from behind the north wall. If anyone in the party has a good engineering skill check, they might notice that a 10 foot section of this wall is a newer addition to the castle. It is covering a tunnel that was build at the same time as the rest of the castle. After a few feet of tunnel, there is a staircase that leads down into the darkness. Thus, the adventure begins.

1) This is the basement of the building in the southeast corner of the courtyard. Behind a new wall is a hallway leading to stairs. Down these long, steep stairs that descend at a 45 degree angle, down a distance of 25ft. At the bottom is a pit that will open up if the trap described in the first section is sprung. It is 10ft across, 5ft wide, and 20ft deep. Across this gap begins the dungeon.

2) This is the first section of dungeon. There are 6 cells, but the locks are rusted and useless. As any good old dungeon, there are undead skeletons that will attack interlopers. There are other dungeon rooms that lead from this, and a two guard rooms.

3) This is the originally constructed entrance to the siege tunnels. It is a secret door in the northern guard post. Unfortunately, this passage has collapsed, making passage impossible without a lot of work clearing the tunnels.

4) This is a large natural cavern that was originally used as a large pit where several prisoners who were not particularly important could all be thrown, and they can kill each other if they like. The entrance is 40ft above the ground, and that wall has been smoothed in an attempt to prevent prisoners from climbing up to the door. One wall of this pit has recently been tunneled through, allowing a juvenile blue dragon to take up residence.

5) This is the siege tunnel built beneath the river. It is well made, and the ground is smooth where rocks have not fallen. It connects to stairs to the north, up which the other side of the cave in can be seen.

6) Here, the original builders of the tunnel ran into a pre-existing series of natural tunnels. These natural tunnels when originally discovered only went a short ways before stopping, so the builders simply build past them and out underneath the river as originally intended. The tunnels continue that way, but another collapse prevents immediate passage.

7) A mighty natural stone pillar dominates the center of this cavern, and several caverns branch off.

8) Side room.

9) More caverns.

10) This room is not natural, and has been carved relatively smooth, but a trap awaits.

11) This tunnel network is mostly underneath the river. Small leaks in the earth have allowed for some of the water to trickle down into a small pool.

12) There is a break in the floor near here, creating a 20ft gap approximately 40ft deep. A strong door blocks the path.

13) This final cavern is a bit of a small, natural wonder. It obviously is older than any other part of the network. Magical lights float through the space, and the stone floor of the rest of the caves is replaced by earth in which trees, grass, and flowers have grown. A crack in the wall lets out a bit of the river above, creating a small waterfall that feeds a pool and stream that winds away into the darkness, through passages too small to follow.

All the doors in this section are mainly still in tact. They are thick, well constructed for the purpose of keeping in prisoners. Most of the locks, however, are now useless. The DM can throw in some working locks if he wants the rogue to have something to do.

Whoever sealed up the dungeon obviously did not want to make it easy for things even to approach the wall. When the party breaks through the wall, a trap goes off. A line of lightning fires through the hallway. But it has been set in such a way as it only would hit someone on the other side of the wall. Thus, an intelligent PC would be able to see that it is likely that the trap was placed here in an attempt to keep something in. There is another trap on the stairs, one set by a clever mage and a skilled stoneworker. DC 27 Search check to see the magical trap, DC 25 Disable Device check. The 25ft long stairs are steep, and the trap goes off when the characters are about half way down. The stairs suddenly shift, turning into a slippery ramp, requiring a DC 30 Balance check to keep from falling. Failing this check requires making a DC 20 Reflex save to keep from sliding down. The slide deposits the party into a 20ft deep, 10ft wide pit that only opens once the trap is sprung. DC 15 Reflex save to grab the edge. The pit has been well carved, and requires a DC 25 to climb. To continue on through the dungeon, the party must find a way across. Once they do this they find themselves in a 30ft hallway, off of which are three cells on either side.

The first room of the dungeons consists of 6 cells. The locks are rusted and useless, but there are a couple good chains. But connected to these chains are six skeletons that rise up to attack. These are human skeletons, but are a bit more powerful than the average human skeleton. Use the stats for a normal human warrior skeleton, except with 3d10 HD (16hp), and a Str score of 15. Instead of scimitars, they use the chains attached by manacles on their wrists as whips, dealing 1d4 bludgeoning damage with a range of 15ft. Each one comes out of one of the cells and attacks as soon as the party enters the room. These should be fairly easy for the party to mop up. There is no treasure reward for this encounter, as it has been added to the rewards later in the adventure.
The rooms directly to the west of this first dungeon are a guardroom connected to two larger, communal dungeon rooms. Not much is in these apart from various filth, and a rat or two. The room to the north is another guardroom, and is the original entrance to the siege tunnels.

A DC 20 Search check will reveal a secret door in the east wall of this room. Once opened, it leads to a passage that connects to the siege tunnels. But a cave in prevents passage much further down this rout.

At the end of the hall is a thick door that leads to the final dungeon. A large, natural cavern has been turned into a pit, a place to throw unimportant prisoners, and who cares if they kill each other. The door opens up 40ft above the floor of the cavern, and the wall that the door is in has been smoothed carefully in order to keep people from climbing it to get to the door. Bones are littered across the floor, and it is obvious that not all of them are old kills. The cavern was originally a dead end, but a hole in the wall of the cavern has recently been made by the now inhabitant of the cavern. This hole leads to a network of natural caverns that also intersects with the siege tunnel. When the party makes it to the floor of the cavern, they are greeted by a juvenile blue dragon coming back through the hole from a hunt, and he is not happy to see intruders in his new lair. He drops the deer carcass he was carrying and attacks. He has only newly acquired this lair, and has not had time to gather the treasure common to dragons. The party only gets half the normal treasure. The difference will be added to the loot at the end of the adventure.

Turning right (west) along this tunnel will take the party to stairs, and above those stairs they will find the other side of the cave in they discovered previously. A gibbering mouther is hanging out here. Heading left (east) along this path would take the party underneath the river, and out of a well hidden cave in the forest. It was through this cave that the dragon got in. But the DM should try to discourage going this way, as there is still a lot more to see down below.

Continuing on through the tunnels north will soon lead the party into a cavern dominated by a large natural pillar in the center, and several passages leading out. This is where the party finds that these caves are inhabited by a party of various devils. Four imps have been doing whatever it is that devils do in the southwest room of the cavern. They attack as the party enters the main cavern, turning invisible and striking from all around. The party kills them and continues on.

This is the hangout spot of the band of devil's second in command. It is a Chain Devil. He will probably hear what has been going on out in the outer cavern, and come out to investigate. More killing, yay. He has some loot on him, but most importantly he has a key. This happens to be the key needed to open the door into section 12, a magically locked door that most lvl 8 characters would have an extremely difficult time opening.

This fun little room has been carved, and is not natural. There is nothing but a chest. A chest and a trap. DC 20 Search check on the chest to find it, DC 23 Disable Device. It is on the hinges of the chest, and is triggered when the chest is opened. The stone door to the room slams shut, and the room fills with water. It takes about 30 seconds fill up, and the 4" stone door has hardness 8, 60hp. Even with the door broken, there is enough water to still be dangerous. There is an entire river above the room, so the party will have an interesting time stopping it once it gets started. Some ideas are trying to block where it is coming from, or blocking the passage. But that makes it difficult to grab the treasure, a ring of protection +1 and a random minor wondrous item.

After crossing a pit (20ft long, 10ft wide, 30ft deep, requiring a DC 20 check to climb). Across this, there is a thick, magic door that would take a DC 50 Str check to break, or a DC 40 Open Lock check. If a spellcaster attempts Dispel Magic or knock and succeeds on a Caster Level check DC 20 will reduce these checks to 20 and 25 respectively. Either way, it is just easier to grab the key in (9). But of course the door is trapped with a fire trap. The party picks themselves up and continues on. There is a small chamber here. There is not much of note, just a few odds and ends. Continuing down the passageway, the party finds another door. It is richly carved out of thick wood, decorated with trees and flowers.

This is the final battle in the adventure.
There are words written on the door in Draconic. Any self-respecting party should have someone who speaks Draconic. And it is a riddle door, because riddle doors are cool. It doesn't make much sense to include a riddle, as I feel the DM should select something appropriate for his/her game. On an incorrect guess of the riddle, the door fires 5 magic missiles at the guesser. When the door opens up, an odd sight greets the party. Beyond the riddle door, the hard stone of the cavern floor has been replaced with soft earth. Strange lights float around the cavern, giving a soft, low light. Grass grows on the earth. The ceiling of the cavern is about 30ft high, and lights play about the ceiling in a perfect replica of the stars in the sky above. On the east side of the cavern there is a small waterfall that feeds a stream that crosses the chamber and runs off into the darkness beyond the light, through passages too small for all but tiny creatures to follow. Trees grow around the pool, and flowers blossom. There is a small, stone bridge across the stream leding to a richly carved wooden table near the northeast wall. This corner is lined with similarly carved bookshelves, covered with books. One thing is certain: this place does not look like it was built by devils. And yet, there one sits. Sitting behind the table is an erinyes. It is not immediately apparent to most people that this is a devil, as she appears as a fairly beautiful human woman in a flowing green dress. A feast worthy of royalty is spread out on the table. The erinyes has been aware of the party's approach for a long while, and has had plenty of time to prepare. She greets the party warmly and kindly, attempting to put the party at ease. The erinyes will attempt to cast Charm Monster on each member of the party, and try to get the party to sit at the table. If a PC successfully uses a Knowledge (planes) check to identify the creature as a devil, that PC gets a +4 to checks against Charm Monster. Even if the party initially succeeds on their saves against Charm Person, if they are foolish enough to eat any of the enchanted food they must make another save as if the spell were cast again. Any PC that eats the food also takes a -4 penalty on Cha saves to avoid doing things they would not normally do (see spell description). The erinyes then offers a deal, a contract written in blood (and all that). She claims that she has the power to give the PCs ownership and dominance over "All that your eyes will ever behold" (wording is important) in exchange for a small, unnamed price, assuring them that it is not their lives, souls, firstborn children, etc. If the PCs are foolish enough to accept, the price turns out to be their eyes. Then they will live the rest of their lives blind, not seeing anything, as the slaves of the erinyes. On a better note, when the party refuses, as they should do if they want to avoid effectively a TPK, the erinyes attacks. Kill her. That should be fun. The food, drink, and dishes disappear upon her death.
Assuming that the party kills her, they will find a lot of value in this room, apart from the room itself. There is a large quantity of non-magical books along the shelves. While the table and shelves can be moved, they refuse to be taken from the room itself. The shelves also have various alchemy equipment. Now for the real loot:
Among the books are tomes (just enough for one per person in the party) that will grant an extra feat (I don't think d&d gives enough feats). In addition, there is another random minor wondrous item, as well as 3000gp around the room. The erinyes has on her person a masterwork longsword and a +1 flaming composite longbow. And that should about do it. Perhaps even a little much.

The party now has several new additions to their castle. They have dungeons, siege tunnels, and caverns. The final room also acts like an alchemists laboratory and magic laboratory, giving a +2 bonus on Craft (alchemy) checks and a +2 bonus on Spellcraft checks made to determine if a new spell is viable.